Can I Belong to Another Church or Religion If I Am Baptized?

Generally speaking, yes. The Lord’s baptism as outlined in 3 Nephi 11 has no conditions against it.

The obvious contradiction would be joining a religion that is openly against Christ and his doctrine to the point you feel it would be counter-productive to your own faith and belief. You may decide on your own what the appropriate particulars are on that, but it is in the spirit of the Book of Mormon to serve others and then you will be in the service of your God (Mosiah 2:17).

Consider the example of Ammon (Alma chapters 17-20), who submitted himself to be a servant of a Lamanite king who supported an apostate system of beliefs. Ammon was able to believe as he wished and yet be willing “to dwell among this people for a time; yea, and perhaps until the day I die” (Alma 17:23), even while considering, “the baseness of the traditions of their fathers, which were not correct” (Alma 17:9). Because of the incorrect traditions of the Lamanites, the Lord told Ammon, “ye shall be patient in long-suffering and afflictions, that ye may show forth good examples unto them in me” (Alma 17:10).

You may hear the call of your Lord to serve among the Catholics, any of the Protestant denominations, or the Evangelicals; the Muslims, the Jews, the Baha’i’s, the Seventh Day Adventists, the Jehovah’s Witnesses, the Amish, the RLDS, or stay LDS, or serve in the Mormon Christian fellowships, or others.

Interestingly, the LDS Church used to (and may still) include as part of their definition of apostasy to “Formally join another church” (See p. 110 at https://file.wikileaks.org/file/mormon-handbook-of-instructions-2006.pdf ). So, if you are LDS, you may be subject to excommunication and being branded as an apostate if you join another church simultaneously.

But again, consider that you just may be considered in good company with the likes of Ammon, and Aaron, and Omner, and Himni, who served among the apostate Lamanites.

Within the other religions, you doubtless will face opposition with false creeds and requirements that challenge your commitment to the doctrine of Christ; but it is a “big brother” attitude, and falsely condemning, for the LDS Church to assume that its members are too immature in the Gospel of Jesus Christ to be able to face those challenges resolutely if they were also members of other churches. As we see with Ammon, there are legitimate, Christ-centered reasons to serve others by becoming one of them. After all, God came among us as one of us. Simply put, it is NOT apostasy to formally join another church. As Jesus said, be as wise as a serpent and harmless as a dove (see Matthew 10:16).